So I have a 71 240 and am doing the R200 Differential Swap.

Fun stuff. I have the newer curved Moustach bar with the bushings facing forward. The question I have is do I need to turn the Diff Mount around to get the extra length so the cross member will line up?

Also what is the little weather van thing attached to the top of the cross member.

I believe the mount does need to be reversed, but since I've never done this mod, you should wait for confirmation from someone who has.

The part you pointed at is the remains of the factory exhaust hanger.

I recently finished this modification, along with several others. Yes, you do turn the mount around so that the differential is further towards the rear of the car. This also aligned my half shafts to eliminate the angularity that was common in older vins. My project also required a longer drive shaft since the diff. was moved rearward.

Do you have any pictures of the completed upgrade?

Specifically the Moustach bar and how it is oriented and the bolts

for the diff mount insulator. I noticed it will be a tight squeeze between the bolts for the

diff mount and the Strap. I saw somewhere that you need to put the bolts going down instead of up to clear the strap.

Sometimes it is necessary to elongate the bolt holes to get proper alignment of the diff mount to the diff itself.

Do what you need to do to get it to fit....and yes the R200 mustache bar is reversed.

I got it to line up. I had to turn the differential mount insulator around so the little F marked on it is pointing to the back of the car. I kept the bolts pointing up and took the strap off for clearance.

Now I just need a later driveshaft as the one from my 71 is short by a inch or two or three.

By the way I have the moustach bar with the stenciled part number on the right side facing the front of the vehicle if anyone is unsure which way it goes for this mod. I had it turned around and it puts the diff too far back.

Edited January 1, 200916 yr by edbud